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| 1 | Leptin: a multifunctional hormone显示文摘Leptin is the protein product encoded by the obese (ob)gene. It is a circulating hormone produced primarily by the adipose tissue. ob/ob mice with mutations of the gene encoding leptin become morbidly obese, infertile, hyperphagic, hypothermic,and diabetic. Since the cloning of leptin in 1994, our knowledge in body weight regulation and the role played by leptin has increased substantially. We now know that leptin signals through its receptor, OB-R, which is a member of the cytokine receptor superfamily. Leptin serves as an adiposity signal to inform the brain the adipose tissue mass in a negative feedback loop regulating food intake and energy expenditure. Leptin also plays important roles in angiogenesis, immune function, fertility and bone formation. Humans with mutations in the gene encoding leptin are also morbidly obese and respond to leptin treatment,demonstrating that enhancing or inhibiting leptin’s activities in vivo may have potential therapeutic benefits. | HUANG Lu, CAI LI(Tel: (214)-648-3340 Fax: (214)-648-9191 E-mail: li03@utsw.swmed.edu)(1 Touchstone Center for Diabetes Research1 Departments of Physiology and,2 Departments of Internal MedicineThe University of Texas Southwestern Medical Center5323 H. | 2000 | Cell Research2000,10,2: | 35 |
| 2 | Seasonal water storage change of the Yangtze River basin detected by GRACE显示文摘US-Germany co-sponsered satellite gravimetry mission GRACE (Gravity Recovery And Climate Experiment), launched in March 2002, has been producing monthly time series of Earth gravity models up to degree and order of 120. The GRACE mission consists of two identical satellites flying on an almost polar orbit with an altitude of about 300-500 km and satelite-to-satellite ranging of about 220 km. Thanks to the payloads of space-borne GPS receivers, accelerometers and high-precision K-band satelite-to-satellite ranging mesurements, GRACE gravity models are expected to achieve more than one order of magnitude of improvement over previous models at spatial scales of a few hundred kilometers or larger. Recovery of surface mass re-distribution based on GRACE’s time-varying gravity models is applied to studies in solid Earth geophysics, oceanography, climatology and geodesy. At secular time scales, GRACE is expected to provide valuable information on global ice changes, whose variations have profound influences on global climate, and in particular, on sea level changes. At seasonal time scales, GRACE is expected to reveal surface water changes with an ac- curacy of less than 1 cm, or ocean bottom pressure changes with an accuracy of less than 1 mbar (1 mbar =102 Pa). These surface mass redistribution measurements would impove our understanding of the global and regional mass and energy cycles that are critical to human life. Using 15 GRACE monthly gravity models covering the period from April 2002 to December 2003, this study compares seasonal water storage changes recovered from GRACE data and hydrology models at global and regional scales, with particular focus on the Yangtze River basin of China. Annual amplitude of 3.4 cm of equivalent water height change is found for the Yangtze River basin with maximum in Spring and Autumn, agreeing with two state-of-the-art hydrology models. The differences between GRACE re- sults and model predictions are less than 1-2 cm. We conclude that satellite gravimetry has huge potentials in monitering water storage changes in large river basins such as Yangtze. | HU Xiaogong1, CHEN Jianli1,2, ZHOU Yonghong1, HUANG Cheng1 & LIAO Xinhao1 1. Center for Astro-geodynamics Research, Shanghai Astronomical Observatory, National Astronomical Observatories, Shanghai 200030, China 2. Center for Space Research, University of Texas at Austin, 3925 W. Braker Lane, Suite 200, Austin, TX78750, USA | 2006 | Science China Earth Sciences2006,49,5: | 29 |
| 3 | Roles of Fas signaling pathway in vitamin E succinateinduced apoptosis in human gastric cancer SGC-7901 cells显示文摘AIM: To investigate the roles of Fas signaling pathway in vitamin E succinate-induced apoptosis in human gastric cancer SGC-7901 cells.METHODS: Human gastric cancer SGC-7901 cells were treated with VES at 5, 10, 20 mg@L-1, succinic acid and vitamin E as vehicle control and condition media only as untreated (UT) control. Apoptotic morphology was observed by DAPI staining. Western blot analysis was applied to measure the expression of Fas, FADD and caspase-8 proteins. After the cells were transiently transfected with Fas and FADD antisense oligonucleotides, respectively, caspase-8 activity was determined by flurometric method.RESULTS: The morphologically apoptotic changes were observed after VES treatment by DAPI staining. 23.7 % and 89.6 % apoptosis occurred after 24 h and 48 h of 20 mg@L-1 VES treatment, respectively. The protein levels of Fas, FADD and caspase-8 were evidently increased in a dose-dependent manner after 24 h of VES treatment. The blockage of Fas by transfection with Fas antisense oligonucleotides obviously inhibited the expression of FADD protein. After SGC-7901 cells were transfected with Fas and FADD antisense oligonucleotides, caspase-8 activity was obviously decreased (P<0.01), whereas Fas blocked more than FADD.CONCLUSION: VES-induced apoptosis in human gastric cancer SGC-7901 cells involves Fas signaling pathway including the interaction of Fas, FADD and caspase-8. | Kun Wu Yao Li Yan Zhao Yu-Juan Shah Wei Xia Lan Zhao,Department of Nutrition and Food Hygiene,Public Health School,Harbin Medical University,Harbin 150001,Heilongjiang Province,China Wei-Ping Yu,Genetics Institute,Texas University of USA,Austin,USA | 2002 | World Journal of Gastroenterology2002,8,6: | 30 |
| 4 | Climate change tendency and grassland vegetation response during the growth season in Three-River Source Region显示文摘Climate change,climate suitablity change for grassland vegetation,and grassland response to climate change during the growth season are studied systematically by using meteorological data of temperature,precipitation,and length of sunlight from 1961 to 2007,NOAA/AVHRR NDVI from 1982 to 2006,and observations of grass height,biomass,and coverage in enclosed grassland from 1994 to 2006.Two models are developed to evaluate climate change and the climatic suitability of grassland vegetation growth.Average temperature,accumulative precipitation,and length of sunlight during the growth season increased from 1961 to 2007 at rates of 0.24°C/10 yr,2.32 mm/10 yr,and 2.81 h/10 yr,respectively.The increase rates of ave-rage temperature between April and May,and between June and August are 0.17 and 0.30°C/10 yr;accumulative rainfall between April and May increased at a rate of 2.80 mm/10 yr,and accumulative rainfall between June and August decreased at a rate of 0.38 mm/10 yr;the increase rates of accumulative length of sunlight between April and May,and between June and August are 2.15 and 1.2 h/10 yr.The climatic suitability of grassland vegetation growth showed an increasing trend,and the increase rate between April and May is greater than that between June and August.Both NDVI observations from 1982 to 2006 and measurements of grass height,dry biomass,and coverage from 1994 to 2006 show that the climate change has resulted in an increase in plant productivity of the grassland in Three-River Source Region.If some protection measures are taken as soon as possible,the deteriorated grassland in Three-River Source Region can recover. | QIAN Shuan1,FU Yang2 & PAN FeiFei3 1 National Meteorological Center,Beijing 100081,China 2 Qinghai Meteorological Research Institute,Xining 810001,China 3 Department of Geography,University of North Texas,Denton,TX 76203,USA | 2010 | Science China Earth Sciences2010,53,10: | 25 |
| 5 | Plasmacytoid dendritic cells in antiviral immunity and autoimmunity显示文摘Plasmacytoid dendritic cells (pDCs) represent a unique and crucial immune cell population capable of producing large amounts of type I interferons (IFNs) in response to viral infection.The function of pDCs as the professional type I IFN-producing cells is linked to their selective expression of Toll-like receptor 7 (TLR7) and TLR9,which sense viral nucleic acids within the endosomal compartments.Type I IFNs produced by pDCs not only directly inhibit viral replication but also play an essential role in linking the innate and adaptive immune system.The aberrant activation of pDCs by self nucleic acids through TLR signaling and the ongoing production of type I IFNs do occur in some autoimmune diseases.Therefore,pDC may serve as an attractive target for therapeutic manipulations of the immune system to treat viral infectious diseases and autoimmune diseases. | TANG Fei1,2,DU Qiumei1,2 & LIU Yong-Jun3 1 Center for Infection and Immunity,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3 Department of Immunology and Center for Cancer Immunology Research,University of Texas,M.D.Anderson Cancer Center,Houston,Texas 77030,USA | 2010 | Science China(Life Sciences)2010,53,2: | 23 |
| 6 | Molecular signal transduction in vascular cell apoptosis显示文摘Apoptosis is a form of genetically programmed cell death, which plays a key role in regulation of cellularity in a variety of tissue and cell types including the cardiovascular tissues. Under both physiological and pathophysiological conditions, various biophysiological and biochemical factors, including mechanical forces, reactive oxygen and nitrogen species, cytokines, growth factors, oxidized lipoproteins, etc., ma influence apoptosis of vascular cells. The Fas/Fas ligand/caspase death-signaling pathway, Bcl-2 protein family/mitochondria, the tumor suppressive gene p53, and the proto-oncogene c-myc may be activated in atherosclerotic lesions, and mediates vascular apoptosis during the development of atherosclerosis. Abnormal expression and dysfunction of these apoptosis-regulating genes may attenuate or accelerate vascular cell apoptosis and affect the integrity and stability of atherosclerotic plaques. Clarification of the molecular mechanism that regulates apoptosis may help design a new strategy for treatment of atherosclerosis and ii major complication, the acute vascular syndromes. | GENG YONG JIAN Center for Cardiovascular Biology and Atherosclerosis Research, Division of Cardiology, Department of Internal Medicine, University of Texas Houston Health Science Center Medical School, 6431 Fannin Street, MSB 6.045, Houston, TX 77030, USA | 2001 | Cell Research2001,11,4: | 20 |
| 7 | USING DISPLACED CONE REPRESENTATION IN DEA MODELS FOR NONDOMINATED SOLUTIONSIN MULTIOBJECTIVE PROGRAMMING显示文摘Concepts revolving around 'displaced cones' are used to extend the ideas of nondominated solutions in multiobjective programming. Necessary and sufficient conditions are formed around the additive models of DEA to idelltify nondominated solutions. This provdes a basis for effecting contacts with other disciplines and other parts of DEA. | W. W. Cooper (Graduate School Of Business, University of Texas at Austin, Austin, Texas, USA 78712-1174)WEI Quanling (Department of Information Management, People’s University of China, Beliing 100872, China) G. Yu (Department of MSIS, University of Texas | 1997 | Systems Science and Mathematical Sciences1997,10,1: | 17 |
| 8 | Immunization with chlamydial plasmid protein pORF5 DNA vaccine induces protective immunity against genital chlamydial infection in mice显示文摘To validate the immune protective efficacy of pORF5 DNA vaccine and to analyze potential mechanisms related to this protection. In this study, pORF5 DNA vaccine was constructed and evaluated for its protective immunity in a mouse model of genital chlamydial infection. Groups of BALB/c mice were immunized intranasally with pORF5 DNA vaccine. Humoral and cell mediated immune responses were evaluated. The clearance ability of chlamydial challenge from the genital tract and the chlamy- dia-induced upper genital tract gross pathology and histopathological characterization were also de- tected. The results showed that the total and the IgG2a anti-pORF5 antibody levels in serum were sig- nificantly elevated after pcDNA3.1-pORF5 vaccination, as were the total antibody and IgA levels in vaginal fluids. pcDNA3.1-pORF5 induced a significantly high level of Th1 response as measured by robust gamma interferon (IFN-γ). Minimal IL-4 was produced by immune T cells in response to the re-stimulation with pORF5 protein or the inactive elementary body in vitro. pcDNA3.1-pORF5-vacci- nated mice displayed significantly reduced bacterial shedding upon a chlamydial challenge and an accelerated resolution of infection. 100% of pcDNA3.1-pORF5 vaccinated mice successfully resolved the infection by day 24. pcDNA3.1-pORF5-immunized mice also exhibited protection against patho- logical consequences of chlamydial infection. The stimulated index was significantly higher than that of mice immunized with pcDNA3.1 and PBS (P<0.05). Together, these results demonstrated that immu- nization with pORF5 DNA vaccine is a promising approach for eliciting a protective immunity against a genital chlamydial challenge. | LI ZhongYu1,2, WANG ShiPing1, Wu YiMou2, ZHONG GuangMing3 & CHEN Ding3 1 Xiangya School of Medicine, Central South University, Changsha 410078, China 2 Department of Microbiology and Immunology, University of South China, Hengyang 421001, China 3 University of Texas Health Science Center at San Antonio, TX 78229, USA | 2008 | Science China(Life Sciences)2008,51,11: | 16 |
| 9 | Automated detection of lunar craters based on object-oriented approach显示文摘The object-oriented approach is a powerful method in making classification. With the segmentation of images to objects, many features can be calculated based on the objects so that the targets can be distinguished. However, this method has not been applied to lunar study. In this paper we attempt to apply this method to detecting lunar craters with promising results. Craters are the most obvious features on the moon and they are important for lunar geologic study. One of the important questions in lunar research is to estimate lunar surface ages by examination of crater density per unit area. Hence, proper detection of lunar craters is necessary. Manual crater identification is inefficient, and a more efficient and effective method is needed. This paper describes an object-oriented method to detect lunar craters using lunar reflectance images. In the method, many objects were first segmented from the image based on size, shape, color, and the weights to every layer. Then the feature of 'contrast to neighbor objects' was selected to identify craters from the lunar image. In the next step, by merging the adjacent objects belonging to the same class, almost every crater can be taken as an independent object except several very big craters in the study area. To remove the crater rays diagnosed as craters, the feature of 'length/width' was further used with suitable parameters to finish recognizing craters. Finally, the result was exported to ArcGIS for manual modification to those big craters and the number of craters was acquired. | YUE ZongYu1,2,3,4, LIU JianZhong3 & WU GanGuo2 1 Institute of Remote Sensing Application, Chinese Academy of Sciences, Beijing 100101, China 2 China University of Geosciences (Beijing), Beijing 100083, China 3 National Astronomical Observatories of Chinese Academy of Sciences, Beijing 100012, China 4 Department of Geological Sciences, The University of Texas at San Antonio, San Antonio, TX 78249, U.S.A | 2008 | Chinese Science Bulletin2008,53,23: | 12 |
| 10 | Free Radical Generation by Selenium Compounds and Their Prooxidant Toxicity显示文摘Selemum (Se) and many of its compounds are among the most toxic of nutrients. Selenium toxicity was first described in range animals in the western United States in the 1930’s which consumed' selenium accumulator' plants of the genus Astragalus, Xylorrhiza,Oonopsis, and Stanleya. Selenites and selenates from the soil accumulate in these plants primarily as methylated selenium compounds and plants evolve dimethyldiselenide and dimethyselenide.Dietary selenium, primarily as selenomethionine and selenocysteine for humans fulfill the dietary requirement for selenoenzymes and proteins. In humans and animals excessive dietary selenium may be toxic. In vitro, selenium compounds such as selenite, selenium dioxide and diselenides react with thiols, such as glutathione, producing superoxide and other reactive oxygen species. This catalytic reaction of selenium compounds with thiols likely accounts for selenium toxicity to cells ex vivo and in vivo where the major glutathione producing organ,the liver, is also the major target organ of selenium toxicity.Selenium enzymes and selenoethers that do not readily form a selenide (RSe-) anion and compounds such as Ebselen where selenium is sequestered, are not toxic. Methylation of selenium by both plants and animals serves to detoxify selenium by generating methylselenides. Alternatively, full reduction of Se to elemental selenium (Se0) as done by some bacteria and the formation of heavy metal selenides such as Ag2Se or Hg2Se, results in a non-catalytic nontoxic form of selenium.This catalytic prooxidant attribute of some selenium compounds appears to account for its toxicity when such activity exceeds plant and animal methylation reactions and antioxidant defenses. This prooxidant activity may also account for cellular apoptosis and may provide a useful pharmaceutical application for selenium compounds as antibacterial, antiviral, antifungal and anticancer | JULIAN E. SPALLHOLZ(Food and Nutrition, Texas Technology University,Lubbock, TX 79404, USA) | 1997 | Biomedical and Environmental Sciences1997,10,2: | 11 |
| 11 | DEGREE OF APPROXIMATION BY SUPERPOSITIONS OF A SIGMOIDAL FUNCTION显示文摘In this paper we study the degree of approximation by superpositions of a sigmoidal function.We mainlyconsider the univariate case.If f is a continuous function,we prove that for any bounded sigmoidalfunction σ,dn,σ(f)≤‖σ‖ω(f,1/(n+1)).For the Heaviside function H(x),we prove that dn,H(f)≤ω(f,1/(2(n+1))).If f is a continuous funnction of bounded variation,we prove that dn,σ(f)≤‖σ‖/(n+1)V(f)and dn,H(f)≤1/(2(n+1))V(f).For he Heaviside function,the coefficient 1 and the approximation orders are the bestpossible.We compare these results with the classical Jackson and Bernstein theorems,and make some conjec-tures for further study. | Chen Debao (University of Texas at Austin,USA) | 1993 | Analysis in Theory and Applications1993,9,3: | 11 |
| 12 | A Spatially Weighted Degree Model for Network Vulnerability Analysis显示文摘Using degree distribution to assess network vulnerability represents a promising direction of network analysis.However,the traditional degree distribution model is inadequate for analyzing the vulnerability of spatial networks because it does not take into consideration the geographical aspects of spatial networks.This paper proposes a spatially weighted degree model in which both the functional class and the length of network links are considered to be important factors for determining the node degrees of spatial networks.A weight coefficient is used in this new model to account for the contribution of each factor to the node degree.The proposed model is compared with the traditional degree model and an accessibility-based vulnerability model in the vulnerabil-ity analysis of a highway network.Experiment results indicate that,although node degrees of spatial networks derived from the tra-ditional degree model follow a random distribution,node degrees determined by the spatially weighted model exhibit a scale-free distribution,which is a common characteristic of robust networks.Compared to the accessibility-based model,the proposed model has similar performance in identifying critical nodes but with higher computational efficiency and better ability to reveal the overall vulnerability of a spatial network. | WAN Neng1,ZHAN F.Benjamin1,2,CAI Zhongliang2 1.School Texas Center for Geographic Information Science,Department of Geography,Texas State University,San Marcos,TX 78666,USA 2.School of Resource and Environmental Science,Wuhan University,129 Luoyu Road,Wuhan 430079,China | 2011 | Geo-Spatial Information Science2011,14,4: | 9 |
| 13 | The effects of vitamin E succinate on the expression of c-jun gene and protein in human gastric cancer SGC-7901 cells显示文摘AIM:Toinvestigate the effects of vitamin E succinate(VES)on the expression of c-jun gene and protein in human gastric cancer SGC-7901 cells.METHODS:After SGC-7901cells were treated with VESat different doses(5,10,20mg·L^-1)at different time,reverse transcription-PCR technique was used to detect the level of c-jun mRNA;Western Blot was applied to measure the expression of c-jun protein.RESULTS:After the cells were theated with VESat 20mg·L^-1for 3h,the expression rapidly reached its maximun that was3.5times of UT control(P<0.01).The level of c-jun mRNA was also increased following treatment of VESfor 6h.However the expression after treatment of VES at 5mg·L^-1for24h was 1.6tmes compared with UTcontrol(P<0.01),Western blot analysis showed that the level of c-jun protein was obviusly elevated in VES-treated SGC-7901cells at 20mg·L^-1for3h,The expression of c-jun protein was gradually increased after treatment of VES at 20mg·L^-1for3,6,12and24h,respectively,with an evident time-effect relationship.CONCONCLUSION:The levels of c-jun mRNA and protein in VES-treated SGC-7901cells were increased in a dose-and time-dependent manner;the expression of c-jun was prolonged by VES,indicating that c-jun is involvedin VES-induced apoptosis in SGC-7901 cells. | Yah Zhao Kun Wu Wei Xia Yu-Juan Shan Li-Jie Wu Department of Nutrition and Food Hygiene,Public Health School,Harbin Medical University,Harbin 150001,Heilongjiang Province,China Wei-Ping Yu Genetics Institute,Texas University of USA,Austin,USA | 2002 | World Journal of Gastroenterology2002,8,5: | 8 |
| 14 | Recent Advances in Swine Amino Acid Nutrition显示文摘Recent advances in swine protein nutrition are characterized by the development of functional amino acids(AA)in regulating fetal and postnatal survival,growth and development.These AA include arginine,glutamine,glutamate,proline,leucine,cysteine and tryptophan.Due to limited knowledge on AA nutrition,pork producers have traditionally paid little attention to supplementing the arginine family of AA to swine diets.Results of recent studies indicate that functional AA serve important regulatory functions in nutrient metabolism,protein turnover,and immune function,therefore enhancing efficiency of feed utilization by pigs.The underlying mechanisms include activation of nitric oxide,mammalian target of rapamycin,gaseous signaling,and AMP-activated protein kinase pathways,as well as anti-oxidative function.Dietary supplementation with arginine,glutamine,proline or leucine to weanling piglets enhances their growth performance.Arginine or glutamine is also effective in increasing milk production by lactating sows.Furthermore,supplementing arginine to the diet of pregnant gilts between days 30 and 114 of gestation increases the number of live-born piglets and litter birth-weight.Availability of feed-grade functional AA holds great promise for improving animal health and nutrient utilization in pig production worldwide.Additionally,feedstuffs of animal origin [e.g.,blood meal(ring dried),feather meal(hydrolyzed),meat and bone meal,porcine protein meal,and poultry by-product meal(both feed-and petfood-grades)] are excellent and cost-effective sources of both essential and functional AA for formulating balanced swine diets.New knowledge on AA nutrition provides a much needed scientific basis for revising the next edition of swine nutrient requirements. | Guoyao Wu Department of Animal Science and Faculty of Nutrition,Texas A&M University,College Station,TX,77843,U.S.A and State Key Laboratory of Animal Nutrition,China Agricultural University,Beijing,100193,China | 2010 | Journal of Animal Science and Biotechnology2010,1,2: | 7 |
| 15 | The Asymptotic Behavior of a Class of Second Order Differential Equation显示文摘In the paper the asympotic behavior of the solution of the following second order differential equation y+ q(t)f(y) =0 is investigated. Some results for asymptotic behavior of the nonoscillation solution are obtained. | FENG Zhao-sheng, WANC Xiao-hui, LI Jin-cheng ( Dept. of Math., Texas A&M University, College Station, TX 77843, USA Dept. of Stat., Texas A&M University, College Station, TX 77843, USA Basic Dep., Tianjin Vocational Tech. & Teaching College, Tianjin 3 | 2001 | Journal of Mathematical Research and Exposition2001,21,3: | 6 |
| 16 | An Analysis of the Meaning of Generics | Mao Yi, Ph.D. of Philosophy received from the University of Texas at Austin, Master of Computer Sciences gained at UT-Austin. Zhou Beihai, Professor of Logic in the Department of Philosophy at Peking University, | 2003 | Social Sciences in China2003,24,3: | 4 |
| 17 | THE BENCHMARK LAND PRICE SYSTEM AND URBANLAND USE EFFICIENCY IN CHINA显示文摘ABSTRACT: China began to introduce market principles and establish price mechanism to better manage land and improve land use efficiency in the late 1980s. Since then, land markets begin to emerge. A benchmark land price system, providing guidelines for land use rights selling and transferring, was established in order to overcome lack of market data and experiences in land transaction. The benchmark prices of land use rights are determined by land use, land use density (floor-land ratio), land grades, land improvement, and tenant resettlement costs. This paper first conducts a formal analysis based on modern urban economic theory. The formal model provides a theoretical foundation in which the benchmark land price system is assessed and evaluated in terms of land use and urban development. The paper then concludes that the benchmark price system has two theoretical problems. One is associated with the fact that floor-land ratio plays an important role in land price determination whereas the theory suggests the other way around. That is, floor-land ratio depends on land prices. The other problem is that the benchmark land price system does not provide adequate room for the substitution between land and capital inputs. The substitution is a key in achieving land use efficiency in land markets and urban development process. It is concluded that the practice of the benchmark land price system is at odd with reforms that aim to introduce market principles and mechanism to guide resource uses. Therefore, it is recommended that further land policy reform should be taken. | DING Cheng-ri(Department of Landscape Architecture and Urban Planning, Texas A &M University, Mail Stop 3137College Station, TX, 77843, USA) | 2001 | Chinese Geographical Science2001,11,4: | 4 |
| 18 | Induced pluripotent stem cell-related genes influence biological behavior and 5-fluorouracil sensitivity of colorectal cancer cells显示文摘Objective:We aimed to perform a preliminary study of the association between induced pluripotent stem cell(iPS)-related genes and biological behavior of human colorectal cancer(CRC) cells,and the potential for developing anti-cancer drugs targeting these genes.Methods:We used real-time reverse transcriptase polymerase chain reaction(RT-PCR) to evaluate the transcript levels of iPS-related genes NANOG,OCT4,SOX2,C-MYC and KLF4 in CRC cell lines and cancer stem cells(CSCs)-enriched tumor spheres.NANOG was knockdowned in CRC cell line SW620 by lentiviral transduction.3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assays,plate colony formation,and a mouse xenograft model were used to evaluate alterations in biological behavior in NANOG-knockdown SW620 cells.Also,mock-knockdown and NANOG-knockdown cells were treated with 5-fluorouracil(5-FU) and survival rate was measured by MTT assay to evaluate drug sensitivity.Results:A significant difference in the transcript levels of iPS-related genes between tumor spheres and their parental bulky cells was observed.NANOG knockdown suppressed proliferation,colony formation,and in vivo tumorigenicity but increased the sensitivity to 5-FU of SW620 cells.5-FU treatment greatly inhibited the expression of the major stemness-associated genes NANOG,OCT4,and SOX2.Conclusions:These results collectively suggest an overlap between iPS-related genes and CSCs in CRC.Quenching a certain gene NANOG may truncate the aggressiveness of CRC cells. | Zhong SHI1,Rui BAI1,Zhi-xuan FU1,Yong-liang ZHU2,Rong-fu WANG3,Shu ZHENG1(1Cancer Institute(Key Laboratory of Cancer Prevention and Intervention,China National Ministry of Education,Key Laboratory of Molecular Biology in Medical Sciences,Zhejiang Province,China),the Second Affiliated Hospital,School of Medicine,Zhejiang University,Hangzhou 310009,China)(2Department of Gastroenterology,the Second Affiliated Hospital,School of Medicine,Zhejiang University,Hangzhou 310009,China)(3Center for Cell and Gene Therapy,Department of Pathology and Immunology,Baylor College of Medicine,Houston,Texas 77030,USA) | 2012 | Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2012,13,1: | 4 |
| 19 | A methodology to determine the elastic properties of anisotropic rocks from a single uniaxial compression test显示文摘This paper introduces a new methodology to measure the elastic constants of transversely isotropic rocks from a single uniaxial compression test.We first give the mathematical proof that a uniaxial compression test provides only four independent strain equations.As a result,the exact determination of all five independent elastic constants from only one test is not possible.An approximate determination of the Young’s moduli and the Poisson’s ratios is however practical and efficient when adding the Saint-Venant relation as the fifth equation.Explicit formulae are then developed to calculate both secant and tangent definitions of the five elastic constants from a minimum of four strain measurements.The results of this new methodology applied on three granitic samples demonstrate a significant stress-induced nonlinear behavior,where the tangent moduli increase by a factor of three to four when the rock is loaded up to 20 MPa.The static elastic constants obtained from the uniaxial compression test are also found to be significantly smaller than the dynamic ones obtained from the ultrasonic measurements. | Morteza Nejati Marie Luise Texas Dambly Martin OSaar | 2019 | Journal of Rock Mechanics and Geotechnical Engineering2019,11,6: | 3 |
| 20 | Structure comparisons of Aedes albopictus densovirus with other parvoviruses显示文摘Parvoviridae is a family of the smallest viruses known with a wide variety of hosts. The capsid structure of the Aedes albopictus C6/36 cell densovirus (C6/36 DNV) at 1.2-nm resolution was obtained by elec-tron cryomicroscopy (cryoEM) and three-dimensional (3D) image reconstruction. Structure compari-sons between the C6/36 DNV and other parvoviruses reveal that the degree of structural similarity be-tween C6/36 DNV and the human parvovirus B19 is higher than that between C6/36 DNV and other in-sect parvoviruses. The amino acid sequence comparisons of structural and non-structural proteins also reveal higher levels of similarity between C6/36 DNV and parvovirus B19 than those between C6/36 DNV and other parvoviruses. These findings indicate that C6/36 DNV is closely related to the human virus B19, and the former might evolve from the human species other than from other insect viruses. | CHENG LingPeng1,2, CHEN SenXiong2, Z. H. ZHOU3 & ZHANG JingQiang2 1 Department of Biomedical Engineering, School of Bioscience & Bioengineering, South China University of Technology, Guangzhou 510640, China 2 State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou 510275, China 3 Department of Pathology & Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX77030, USA | 2007 | Science China(Life Sciences)2007,50,1: | 3 |